rondubbs

Anyone care to explain how these things relate? why can you increase timing without pinging if you use high octane?? etc...

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1988 GTA Trans Am 350tpi: 48k miles,3:27 BW rear, aftermarket t-tops
Hotchkis: subframe connectors & strut tower brace
Flowmaster: 3inch exhaust& dual chamber muffler
Accel: 8.8mm wires, cap&rotor, u-groove spark plugs
Edelbrock: 52mmTB, intake & runners
K&N: filtercharger
TPIS: 170* stat, afpr, mat relocation kit
March: performance crank and alternator pulleys
Hypertech: 176* fan switch
Other mods: ported plenum, gutted cat, tb coolant bypass, homemade cold air induction, flux capacitor@ 1.21jW, driver side floor mat removed
1/4 mile - 14.58

AlkyIROC

Octane is the fuels resistance to detonation. It does this by burning slower. Since it takes longer to burn the same amount of fuel, timing can be increased allowing more time for the fuel to burn before the piston reaches TDC. Higher octane can also use higher compression since the fuel won't pre-ignite when compressed. Higher octane is also required for any kind of power adder (NOS, supercharger etc) for the same reason. Higher cylinder pressure will ignite lower octance fuels before the spark plug will.

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and check out the race car

87 IROC-Z SuperPro ET Bracket Race Car
461 naturally aspirated Big Block

Best ET on a time slip: 11.242 altitude corrected to 10.89
Best MPH on a time slip: 121.52 altitude corrected to 125.89
Altitude corrected rear wheel HP: 481.6
Best 60 foot: 1.546

Racing at 3500 feet elevation but most race days it's over 5000 feet density altitude!
Member of the Calgary Drag Racing Association

87 IROC bracket car, 91 454SS daily driver, 95 Homebuilt Harley

purpleworm

Damn i have to say very good explanation!